Try Rector Online | Rector - Automated Way to Instantly Upgrade and Refactor any PHP code

Run Rector on your code to see what it can do for you:

// no change

PHP snippet to change

<?php

final class DemoFile
{
    public function run()
    {
        if (!isset($var)) {
            $var = 'zzz';
        }
    }
}

Config rector.php

<?php

use Rector\Config\RectorConfig;
use Rector\Php74\Rector\Assign\NullCoalescingOperatorRector;
use Rector\ValueObject\PhpVersion;

return RectorConfig::configure()
    ->withRules([
        NullCoalescingOperatorRector::class
    ]);

Rector version: 2.5.4 - released at 2026-07-05 23:08